Magnetic recorder



' F. L. DYER MAGNETIC RECORDER June 30, 1925. 1,544,379"

Filed Feb. 16, 1921 gvweutoz Patented in. 30, 1925.

manic 1.; m, or moN'rcLAm, NEW mns'nz.

MAGNETIC RECORDER.

Application filed Tebruary 1a, 1921. Serial No. 445,416.

To all whom it may concern: Be it known that I, FRANK L. DYER, a

citizen of the United States, and residing at by operating a cutting stylus by .means of.

telephonic currents to thereby form: in a solid material a groove having vertical or lateral variations, corresponding to .sounds;

and from which master xrecord duplicate copies in hard material may be made by well- 1 known processes. Preferably the-telephonic currents. are amplified by means of oneor' v more amplifiers, as disclosed iii application a of Vreeland and Dyer, filed March 14,1919,

Serial No. 282,610, to thus provide currents of substantial energy and bymeans ofwhich a soundgroove of substantial amplitude, and

- 26 of great accuracy may be produced.

- My improved magnetic recorder provides the following features: 1

' 1. A polarized recorder is used by which the movements of. the stylus in both direc- 80 tions will be positivelypefiected. \Vith an non-polarized device, the movement in one direction is 'efl'ected magnetically, the movement in the opposite direction being -effected by means of a spring, and in" consequence the recording is not accurate and the styius is not under accurate and delicate contro 2.'The stylus is. carried by a reed or tongue which is substantially aperiodic and Hence. is substantially non-resonant.

3. Provisionis made in a magnetic 'recorder for permitting the stylus to lightly engage the recording material with suflicient pressure for the desired cut, and at the same time having the desired fioating effect, so as to be unaffected by warping or other surfaceirregularities of the recording material. vAt the same time provision is made for proper adjustment of the reed or tongue relatively to the actuating magnet or magnets as to preserve the desired relationship between them. L 4. Provision'is made for determining with accuracy the desired location of the arma- 65 'ture between the magnet poles to secure close to its diameter.

proper, uniform two magnets. I 5. I mount the cutting stylus on-or near the forward end of the reed or tonguewhereby under the relatively high recording speed the shavings will be thrown upwards. and

away fromthe vibrating elements. It is especially important that mo mechanical obstruction shall lodge in the very narrow space in which the armature vibrates. Preferably provision is 'made byvacuum to cleanly remove all shavings as fast as formed and equal'operation by the from the neighborhood of the vibrating v parts.

-My -ob'j ect @gen erally stated is to provide a magnetic recorder having the features'of construction above referred to, as well as others to be more fully hereinafter described.' v i In the .dra'wing:

netic recorder, showingits operation in mak .ing a talking mechine record.

Fig. 2 an enlarged .front elevation, partly.

in section, showingthe magnets and allied parts, and illustrating the determining de-v vice for centering the reed or tongue, I Fig.3, a side view on .the same scalefas Fig. 2, partly in section, showing the vacuum pipe in position and .Fig. 4, a sectional View on the line 44 of Fig. 3. r

In all of the above views corresponding parts are represented by thesame numerals. T heblank 1 of suitable recordin material is carriedupon'a rotating turn-ta 1e 2, and the cutting stylus 3 engagesthe blank at or The turn-table is rotated, and at the same time relative hori} zontal movement takes-place between the blankand the cutting stylus so as to cut;

a spiral groove in the blank. In the'drawreason of the fact that the turn-table moves longitudinally with respect to the cutting tool. F or is purpose the turn-table is mounted in a frame 4 and isrotated by a .ing this relative, movement takes place by suitable motor or other driven or driving 75 5 Fig. 1 is aside-view of my improved mag;

V with ahead 9, which is secured to a slide 10. The slide is adjustable vertically by.

I means of an adjusting screw 11. Mounted at the lower end of the slide 10 is ayoke 12, capable ofslight horizontal adjustment therein. This adjustment is effected in any suitable way, as by an adjusting screw 13,

.shown being merely for the purpose of illustration.

, The yoke 12 carries two coils 15, ,15, magnetizing the two poles-16, 16, which-areextended inwardly as shown in Fig. 2, and form a very narrow gap between them. In

' Fig. 2this gap is. shown as greatly exaggerated for the purpose of clearness. The

2 vibi ation of the armature between the poles is of the order of one or two thou'sandths of an inch, and hence the free, space between the armature and the pole faces is very slight. Theslide '10, yoke 12 and poles 16 are all formed of iron or other magnetic material. Extending from the lowerend. of

the slide 10is a permanent magnet 17 hav ing a down'turned leg, as shown, and carry.-

ing brackets 18' in which are pivots 19, 19-

for a rock shaft ,20. This rock shaft is probelow thegvertical leg of the magnet, the

magnetic pull will neutralize the Weight on the pivots 19 to., thus reduce friction. The

'hub 21 carries the tongue or reed 22, whose forward end is enlarged'to form an armature 23. Preferably the armature andreed are integral, but at least ,,the armature, should be made magnetic. By reducing the thickness of the armature-at the reed portion 22,

the device will be substantially aperiodic and hence non-resonant. The stiffness of the reed is sufficient to normally maintain the armature in its desired central position between the twopoles 16, 16.

Thecutting stylus 3 is carried by and vibrates with the armature being located at the en'd of the armature and facing forwards so that any shavings will be deflected upwards and out of the way of the rotating parts. The ordinary cutting speeds used in "making talking machine records are such as to cause the shavings to'be thus thrown upwards as a pra'ctically'continuous stream.

It is highly important that no shavings should lodge withinthe narrow space in which the armature vibrates and therefore 'I prefer to use-a vacuum pipe 24 to .draw' I V the shavings away "and removethem clear of the apparatus. The lower end of the vacuum pipe 2-:t'is removablycarried with in guldes 25 (see Fig; 4) secured to a plate 25,

Any appropriate I depending from the yoke 12. This plate is formed with an index 27 located immedi- The weightof the armature 23 and cut ting tool 3 may be made sufficient'to cause the stylusto engage to'the correct depth in the' recording material, but preferably I employ a spring 29 to' supplement this weight, which'spring is adjusted by ascrew 4 .30 so that the cutting depth can in this way be accurately regulated. It is preferable to have the.cutting depth thus controlled by spring J action rather than by depending upon the Weight'bf the parts so as 'to thus prevent inertia from interfering with the operation. The cutting stylus can be elevated from the blank in any suitable way,

as for example, .by a lever 31 connected to \the hub 21 and engaged by a lever 32, operated by a finger piece 33. By providing magnetic poles 16 can bekept always in.

for'vertical adjustment of theslide 10' tha -.proper relation to the armature 23, any

vided with an enlarged hub 21 working "el'tical B QQ S 9 re being within a slotin the vertical leg of the mag 'Q IIISe relatlvely 1ncol1S1derable.

net 7. By locating the shaft 20 and hub-21 It will not be'necessary to describe in detail the electric connections since the operation of the polarized magnets is the same aswith the well-known telegraph polarized reby Letter Patent, is as follows:

1. ln=armagnetic recorder, the combination with polarized magnets, an aperiodic armature operated thereby and freely movable a plane parallel to the polar faces,

.and a cutting tool carried by the armature,

substantially as set forth.

2. a magnetic recorder, the'combina tion with magnet, anal-mature actuated thereby, said armature being vibratable.

sand from the polar faces and being.

towar freely movable in a plane parallel to the polar face, and a cuttin stylus carriedby the armature,-substantial y as set forth.

3. In a 'magnetic'recorder, the combination with a magnet, of an armature vibratable towards andJfrom the polar face and freely movable in a plane parallel to the polar face,.a cutting stylus carried by the armature, and means for adjusting the mag net in a plane parallel-with its polar face, substantially as set forth.

. 4. In a magnetic recorder, the combination of polarized magnets having opposed polar faces and influenced by telephone curpolar faces, substantially as set forth.

- 5. In a magnetic recorder, the combination with a magnet, an armature vibratable towards and from its polar face, a cuttin stylus carried by the armature and locate to cause shavings to be directed away from.

' the magnet, and a suction pipe removably polar face and vibrating by the the depth of cut of the cutting stylus, sub--,

carried by the magnet and into which the shavings are directed, substantially as set 1 forth.

6. In a magnetic recorder, the combina-' tion with a magnet, a pivoted armature movable freely in a plane parallel with the towards and away from'the polar face, a butting stylus carried armature, and meansfor regulating stanti'ally asset forth.

the polar face,

the armature, and an adjustable spring for adjusting the magnets with respect 7 In a magnetlc recorder, the combination with a magnet, a. pivoted armature mov-' able freely in a plane parallelwiththe polar face and vibrating towards and away from a cutting stylus carried by regulatin 'the depth of cut of the cutting stylus su stantially: as set forth.

8. In a recording apparatus the'combin'ation of polarized magnets, an armature lo-' cated between the magnetic poles, means for to the armature to locate the armature centrally between the poles, and a cutting stylus carriedby 'the armature, substantially as set l forth; 40

'9'.- In amagnetic recorder the combinationdf polarized magnets, an armature located.

between the magnetic poles and pivoted so .as to move freely *in a plane parallel to the .polar faces said armature beingvibrate'd towards and away from the. polar faces and a-cutting stylus carried" by the armature, su stantially as set forth.

10. In a recording apparatus the combinaQ means tion of polarized magnets, a permanent. magnet. cooperating therewith, an armature pivoted upon the permanent magnet to move freely in a" plane parallel to the polar faces of they polarized magnets and a cuttingstylus carried by said armature, substantially as set forth. .f

12. Ina magnetic recorder the combina tion of polarized net cooperating.

shaft, the weight of which. is neutralizedv by the magnetic pull, an armature carried; by he shaft and movable freely in a plane parallel to the. polar-faces of the polarized magnets, and a cutting stylus carried by said armature, substantially'as set forth.

13. In a magnetic recorder, the combina--.

freely in ,a' plane parallel to' the polar faces fa'ce, abutting stylus carriedloy the armature, and means for manually moving the magnets, a permanent mag: I therewith, a pivoted rock and .vibratabl'e towards and from the polar armature in av plane parallel to'fthe.polar face, substantially'as set forth.

1 f. In a magnetic recorder, the combination'of' polarized magnets, of an armature located between the polar faces and freely movable-in. a plane parallel with the. polar faces, a cutting stylus carriedrby the arma- 'ture,

tia'llyas setforth. j This specification signed and' witnessed this 14th day of February, 1921. i j FRANKLDYER. Witnesses':

".CHARLES C.

and means for adjusting the magnets both vertically and horizontally, substan- 

